Just to add, I think there's also a plugin for Inkscape that imports layers to Moho/AS. I also think I recall (some time since I've had to do it) that if you import an .svg it imports layers as objects all on the one layer. You theoretically can use Scripts>Layer Effects>RT:Break Apart Shapes to convert the objects to layers, success depending on how you've organised your Illustrator/Inkscape file - probably a bit of a mess if you're importing 3d objects.